One of the many observations I made while walking on The Camino is how the equipment you carry affects your experience. For example, the kind of poles or walking stick you use is a big indicator of how you walk.
The most popular choice is a pair of collapsible hiking poles, which from appearance seems to have been developed from skiing poles. Adjustable to your own height, but generally to about the height of your elbow, the poles act like a second pair of feet. The help to carry thirty percent of your weight, which is a great help when walking with a backpack. Normally these have metal tips which can be thrust into sand, soil, and snow. They can also have rubber tips which can pop on and off, so they can be used on pavement.
The other choice is a classic walking stick or staff. These can be from elbow height to as tall as your are (one gentleman had one a foot and a half taller than himself.) Shod with a metal tip, the wood staff has a leather thong which wraps around the hand, and can be decorated with a gourd or shell, the classic icon of the Peregrino. They are also much cheaper to get, and some folk just improvise a staff from a branch they pick up off the trail.
Each choice has it’s own style of walking. The double poles reflect the left, right, left, right motion of your feet. Depending on the terrain they can either jab into the ground for support, push off for speed, or lightly tap the ground for pace. The classic staff is held in a much lighter grip, and is used to tap the ground for pace or probe ahead for support.
From observation, the people who choose the single staff are much more experienced walkers. They generally walk faster, with a much more even gait, and use the staff only on occasion to support their weight. The double pole users, on the other hand, can use their entire body to propel themselves and support and balance the load of their backpacks. And for an inexperienced or heavier walker, the poles can be a lifesaver.
Of course, I have seen a few that choose to walk without the poles or staff. To each their own.